Convert mainstone to use the MAX1600 library and gpiod APIs for socket
status and control signals.
Acked-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Convert Neponset to use the gpiod API to specify which GPIOs are used
for PCMCIA, and use the MAX1600 power switch library for Neponset,
simplifying the neponset pcmcia driver as a result.
Acked-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Convert the low level PCMCIA driver to gpiod APIs for controlling
the socket power.
Acked-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Add a library for the MAX1600 PCMCIA power switch device. This is a
dual-channel device, controlled via four GPIO signals per channel.
Two signals control the Vcc output, and two control the Vpp output.
Acked-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Simplify the code by getting rid of the conditional automatic
registration of the sa11x0 PCMCIA interfaces in sa1100_init(), and
require all platforms to explicitly call sa11x0_register_pcmcia().
Only one platform (iPAQ) is affected by this change.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Clearing cpenable special register for a task without changing
coprocessor owner for the coprocessors that were enabled will result in
coprocessor context flush and immediate reload at the next attempt to
access this coprocessor if it happens before the context switch.
Avoid it by only clearing cpenable special register if
coprocessor_release_all is called for the current task.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Use addresses instead of offsets and drop unneeded offset -> address
calculations. Don't generate any code for undefined coprocessors.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
WSR and RSR are too generic and collide with other macro definitions in
the kernel causing warnings in allmodconfig builds. Drop WSR and RSR
macros and WSR_* and RSR_* variants. Change get_sr and set_sr to
xtensa_get_sr and xtensa_set_sr. Fix up users.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
After commit d202cce896, an expired cache_head can be removed from the
cache_detail's hash.
However, the expired cache_head may be waiting for a reply from a
previously submitted request. Such a cache_head has an increased
refcounter and therefore it won't be freed after cache_put(freeme).
Because the cache_head was removed from the hash it cannot be found
during cache_clean() and can be leaked forever, together with stalled
cache_request and other taken resources.
In our case we noticed it because an entry in the export cache was
holding a reference on a filesystem.
Fixes d202cce896 ("sunrpc: never return expired entries in sunrpc_cache_lookup")
Cc: Pavel Tikhomirov <ptikhomirov@virtuozzo.com>
Cc: stable@kernel.org # 2.6.35
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
According to eDP spec, sink can required specific selective update
granularity that source must comply.
Here caching the value if required and checking if source supports
it.
v3:
- Returning the default granularity in case DPCD read fails(Dhinakaran)
- Changed DPCD error message level(Dhinakaran)
v4:
- Setting granularity to defaul when granularity read is equal to
0(Dhinakaran)
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181204003403.23361-9-jose.souza@intel.com
Selective updates have a default granularity requirements as stated
by eDP spec(PSR2 SELECTIVE UPDATE X GRANULARITY CAPABILITY register
definition), so check if HW can match those requirements before
enabling PSR2.
v3:
- Changes in the comments and commit message(Dhinakaran)
- Printing the hdisplay that do not match with default granularity
Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181204003403.23361-8-jose.souza@intel.com
Source is required to comply to sink SU granularity when
DP_PSR2_SU_GRANULARITY_REQUIRED is set in DP_PSR_CAPS,
so adding the registers offsets.
v2: Also adding DP_PSR2_SU_Y_GRANULARITY(Rodrigo)
Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181204003403.23361-7-jose.souza@intel.com
Our frontbuffer tracking improved over the years + the WA #0884
helped us keep PSR2 enabled while triggering screen updates when
necessary so this FIXME is not valid anymore.
Acked-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181204003403.23361-6-jose.souza@intel.com
For ICL the bit 12 of CHICKEN_TRANS is reserved so we should not
touch it and as by default VSC_DATA_SEL_SOFTWARE_CONTROL is already
unset in gen10 + GLK we can just drop it and fix for both gens.
Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181204003403.23361-5-jose.souza@intel.com
eDP spec states 2 different bits to enable sink to trigger a
interruption when there is a CRC mismatch.
DP_PSR_CRC_VERIFICATION is for PSR only and
DP_PSR_IRQ_HPD_WITH_CRC_ERRORS is for PSR2 only.
Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181204003403.23361-4-jose.souza@intel.com
As we have a else block for the 'if (dev_priv->psr.psr2_enabled) {'
and this bit is only set for PSR1 move it to that block to make it
more easy to read.
Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181204003403.23361-3-jose.souza@intel.com
For PSR2 there is no register to tell HW to keep main link enabled
while PSR2 is active, so don't configure sink DPCD with a
misleading value.
v2: Moving the set of DP_PSR_CRC_VERIFICATION to the else block
of 'if (dev_priv->psr.psr2_enabled)' to another patch. (Rodrigo)
Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181204003403.23361-2-jose.souza@intel.com
i915 yet don't support PSR in Apple panels, so lets keep it disabled
while we work on that.
v2: Renamed DP_DPCD_QUIRK_PSR_NOT_CURRENTLY_SUPPORTED to
DP_DPCD_QUIRK_NO_PSR (Ville)
v3:
Adding documentation to DP_DPCD_QUIRK_NO_PSR(Dhinakaran and Jani)
Fixed typo in comment of the new quirk entry(Jani)
Fixes: 598c6cfe06 (drm/i915/psr: Enable PSR1 on gen-9+ HW)
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181204003403.23361-1-jose.souza@intel.com
[Why]
New GCC warnings for stringop-truncation and stringop-overflow help
catch common misuse of strncpy. This patch suppresses these warnings
by fixing bugs identified by them.
[How]
Since the parameter passed for name in amdpgu_dm_create_common_mode has
no fixed length, if the string is >= DRM_DISPLAY_MODE_LEN then
mode->name will not be null-terminated.
The truncation in fill_audio_info won't actually occur (and the string
will be null-terminated since the buffer is initialized to zero), but
the warning can be suppressed by using the proper buffer size.
This patch fixes both issues by using the real size for the buffer and
making use of strscpy (which always terminates).
Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
add protection code to avoid lower frequency trigger over drive.
Reviewed-by: Rex Zhu <Rex.Zhu@amd.com>
Signed-off-by: Tianci Yin <tianci.yin@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
KIQ in VF’s init delayed by another VF’s reset,
which would cause late_init failed occasionally.
MAX_KIQ_REG_TRY enlarged from 20 to 80 would fix this issue.
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Wentao Lou <Wentao.Lou@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Document the devm_of_clk_del_provider and the
devm_of_clk_add_hw_provider functions.
Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
[sboyd@kernel.org: Comply with kernel-doc formatting]
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
From Yishai,
-----------------------------------
This series enriches DEVX support in few aspects: it enables interoperability
between DEVX and verbs and improves mechanism for controlling privileged DEVX
commands.
The first patch updates mlx5 ifc file.
Next 3 patches enable modifying and querying verbs objects via the DEVX
interface.
To achieve that the core layer introduced the 'UVERBS_IDR_ANY_OBJECT' type
to match any IDR object. Once it's used by some driver's method, the
infrastructure skips checking for the IDR type and it becomes the driver
handler responsibility.
The DEVX methods of modify and query were changed to get any object type via
the 'UVERBS_IDR_ANY_OBJECT' mechanism. The type checking is done per object as
part of the driver code.
The next 3 patches introduce more robust mechanism for controlling privileged
DEVX commands. The responsibility to block/allow per command was moved to be
done in the firmware based on the UID credentials that the driver reports upon
user context creation. This enables more granularity per command based on the
device security model and the user credentials.
In addition, by introducing a valid range for 'general commands' we prevent the
need to touch the driver's code any time that a new future command will be
added.
The last patch fixes the XRC verbs flow once a DEVX context is used. This is
needed as XRCD is some shared kernel resource and as such a kernel UID (=0)
should be used in its related resources.
Thanks
Yishai Hadas
-----------------------------------
The top 6 patches are the mlx5-devx series, the remainder are from the
mlx5-next tree as the mlx5-devx series depended on the mlx5-next
mlx5_ifc file update.
* mlx5-devx: (42 commits)
IB/mlx5: Allow XRC usage via verbs in DEVX context
IB/mlx5: Update the supported DEVX commands
IB/mlx5: Enforce DEVX privilege by firmware
IB/mlx5: Enable modify and query verbs objects via DEVX
IB/core: Enable getting an object type from a given uobject
IB/core: Introduce UVERBS_IDR_ANY_OBJECT
net/mlx5: Update mlx5_ifc with DEVX UCTX capabilities bits
RDMA/mlx5: Unfold modify RMP function
RDMA/mlx5: Unfold create RMP function
RDMA/mlx5: Initialize SRQ tables on mlx5_ib
RDMA/mlx5: Update SRQ functions signatures to mlx5_ib format
RDMA/mlx5: Use stages for callback to setup and release DEVX
RDMA/mlx5: Remove SRQ signature global flag
net/mlx5: Move SRQ functions to RDMA part
net/mlx5: Remove references to local mlx5_core functions
net/mlx5: Remove not-used lib/eq.h header file
net/mlx5: Remove dead transobj code
net/mlx5: Align SRQ licenses and copyright information
net/mlx5: Debug print for forwarded async events
net/mlx5: Forward SRQ resource events
...
Signed-off-by: Doug Ledford <dledford@redhat.com>
amdgpu_xgmi_update_topology is called both on device registration
and reset. Fix misleading print since the device is added only once to
the hive on registration and not on reset.
Signed-off-by: Andrey Grodzovsky <andrey.grodzovsky@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Move trivial RTCs to the rtc generic binding documentation as they all also
support at least 'start-year'.
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Rob Herring <robh@kernel.org>
For selftests like live_hangcheck, which does thousands of reset per
second, it is too verbose to log every time we re-apply the workarounds.
Remove those messages since, coupled with the dedicated selftest, it is
sufficient to only log the number of recorded workarounds at init time.
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Suggested-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20181204171530.28583-1-tvrtko.ursulin@linux.intel.com
Allows XRC usage from the verbs flow in a DEVX context.
As XRCD is some shared kernel resource between processes it should be
created with UID=0 to point on that.
As a result once XRC QP/SRQ are created they must be used as well with
UID=0 so that firmware will allow the XRCD usage.
Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Update the supported DEVX commands, it includes adding to the
query/modify command's list and to the encoding handling.
In addition, a valid range for general commands was added to be used for
future commands.
Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Enforce DEVX privilege by firmware, this enables future device
functionality without the need to make driver changes unless a new
privilege type will be introduced.
Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Enables modify and query verbs objects via the DEVX interface.
To support this the above DEVX handlers were changed to get any
object type via the UVERBS_IDR_ANY_OBJECT mechanism.
The type checking and handling is done per object as part of the
driver code.
Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Enable getting an object type from a given uobject, the type is saved
upon tree merging and is returned as part of some helper function.
Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Introduce the UVERBS_IDR_ANY_OBJECT type to match any IDR object.
Once used, the infrastructure skips checking for the IDR type, it
becomes the driver handler responsibility.
This enables drivers to get in a given method an object from various of
types.
Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
If the user did setup polling in the driver we should not require
another know in the block layer to enable it.
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This avoids having to have differnet mq_ops for different setups
with or without poll queues.
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This was intended to support users like nvme multipath, but is just
getting in the way and adding another indirect call.
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The ->poll_fn has been stale for a while, as a lot of places check for mq
ops. But there is no real point in it anyway, as we don't even use
the multipath code for subsystems without multiple ports, which is usually
what we do high performance I/O to. If it really becomes an issue we
should rework the nvme code to also skip the multipath code for any
private namespace, even if that could mean some trouble when rescanning.
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The code was always a bit of a hack that digs far too much into
RDMA core internals. Lets kick it out and reimplement proper
dedicated poll queues as needed.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Now that we can't poll regular, interrupt driven I/O queues there
is almost nothing that can race with an interrupt. The only
possible other contexts polling a CQ are the error handler and
queue shutdown, and both are so far off in the slow path that
we can simply use the big hammer of disabling interrupts.
With that we can stop taking the cq_lock for normal queues.
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This is the last place outside of nvme_irq that handles CQEs from
interrupt context, and thus is in the way of removing the cq_lock for
normal queues, and avoiding lockdep warnings on the poll queues, for
which we already take it without IRQ disabling.
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pass the opcode for the delete SQ/CQ command as an argument instead of
the somewhat confusing pass loop.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We have three places that can poll for I/O completions on a normal
interrupt-enabled queue. All of them are in slow path code, so
consolidate them to a single helper that uses spin_lock_irqsave and
removes the fast path cqe_pending check.
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This will allow us to simplify both the regular NVMe interrupt handler
and the upcoming aio poll code. In addition to that the separate
queues are generally a good idea for performance reasons.
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Use a bit flag to mark if the SQ was allocated from the CMB, and clean
up the surrounding code a bit.
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This gets rid of all the messing with cq_vector and the ->polled field
by using an atomic bitop to mark the queue enabled or not.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Having another indirect all in the fast path doesn't really help
in our post-spectre world. Also having too many queue type is just
going to create confusion, so I'd rather manage them centrally.
Note that the queue type naming and ordering changes a bit - the
first index now is the default queue for everything not explicitly
marked, the optional ones are read and poll queues.
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The enhanced devx support series needs commit:
9d43faac02 ("net/mlx5: Update mlx5_ifc with DEVX UCTX capabilities bits")
Signed-off-by: Doug Ledford <dledford@redhat.com>
Add command definition for security commands defined in Intel DSM
specification v1.8 [1]. This includes "get security state", "set
passphrase", "unlock unit", "freeze lock", "secure erase", "overwrite",
"overwrite query", "master passphrase enable/disable", and "master
erase", . Since this adds several Intel definitions, move the relevant
bits to their own header.
These commands mutate physical data, but that manipulation is not cache
coherent. The requirement to flush and invalidate caches makes these
commands unsuitable to be called from userspace, so extra logic is added
to detect and block these commands from being submitted via the ioctl
command submission path.
Lastly, the commands may contain sensitive key material that should not
be dumped in a standard debug session. Update the nvdimm-command
payload-dump facility to move security command payloads behind a
default-off compile time switch.
[1]: http://pmem.io/documents/NVDIMM_DSM_Interface-V1.8.pdf
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Impose a restraint that we have all vma pinned for a request prior to
its allocation. This is to simplify request construction, and should
facilitate unravelling the lock interdependencies later.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181204141522.13640-3-chris@chris-wilson.co.uk
In commit 4721a60109, we tried to fix a problem wherein directio reads
into a splice pipe will bounce EFAULT/EAGAIN all the way out to
userspace by simulating a zero-byte short read. This happens because
some directio read implementations (xfs) will call
bio_iov_iter_get_pages to grab pipe buffer pages and issue asynchronous
reads, but as soon as we run out of pipe buffers that _get_pages call
returns EFAULT, which the splice code translates to EAGAIN and bounces
out to userspace.
In that commit, the iomap code catches the EFAULT and simulates a
zero-byte read, but that causes assertion errors on regular splice reads
because xfs doesn't allow short directio reads. This causes infinite
splice() loops and assertion failures on generic/095 on overlayfs
because xfs only permit total success or total failure of a directio
operation. The underlying issue in the pipe splice code has now been
fixed by changing the pipe splice loop to avoid avoid reading more data
than there is space in the pipe.
Therefore, it's no longer necessary to simulate the short directio, so
remove the hack from iomap.
Fixes: 4721a60109 ("iomap: dio data corruption and spurious errors when pipes fill")
Reported-by: Murphy Zhou <jencce.kernel@gmail.com>
Ranted-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
